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cable barrier line post footing design

Question
State WI
Description Text
At our pooled fund meeting, MwRSF indicated that they have done some work on line post anchors designs. The design that you have come up still have some cracking issues but it is an improvement to what we have seen. I was wondering if I could get a CADD design of the drawing. I was wondering how I could write specifications to get manufacturers to design similar line posts.





Date May 2, 2013
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During our evaluation of the socketed foundations for cable posts, we aimed to simulate a worst-case impact to the post/foundation while preventing both damage and displacement.  Testing was conducted with a bogie vehicle equipped with a rigid impact head centered 12" above ground line impacting the post at a target speed of 20 mph.  Note, weight of the bogie was around 1,800 lb, but lighter surrogate vehicles would be applicable as long as they have enough energy to bend and ultimately override the post.  This impact was created to replicate small car bumper or bottom frame impacts.

The foundations were evaluated for both damage and displacement. Displacements less than 1" were considered acceptable, although less than 1/2" were desired.  Foundations with more that 1" of displacement were considered to shallow and/or narrow to prevent excessive movements that would require the foundation to be reset during barrier repair.  Similarly, damage was to be held to a minimum so as to not require repairs. It was determined that cracking and small scale concrete spalling or chipping would be allowable.  Large concrete fractures would be deemed a structural failure.

The foundations have not been finalized at this time.  Once they are finalized, I can get you the CAD drawings.

Date May 13, 2013
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